Image copyrightDaza et al/Sci AdvancesImage caption
The fossils date back to 99 million years ago

Lizards locked in amber for 99 million years give a glimpse of a "lost world", say scientists.

The ancient reptiles are preserved in "superb detail" down to scales of skin, the tip of a tongue and tiny claws.

Two of the fossils are related to modern-day chameleons and geckos, revealing how features such as sticky toe-pads evolved.

The lizards inhabited tropical forests in what is now Myanmar during the Mid-Cretaceous Period.

Researchers in the US have published their assessment of the specimens in the journal Science Advances.

"The fossilised amber provides a view into a lost world, revealing that the tropics of the Mid-Cretaceous contained a diverse lizard fauna," Dr Edward Stanley of the Florida Museum of Natural History told BBC News.

Some of the lizards are representatives of modern groups such as geckos, while others have no modern equivalent and eventually died out.

One of the fossils appears to be a transitional form between the "standard" lizard form and chameleons, said Dr Stanley.

"This 'missing-link' is roughly 80 million years older than the next oldest chameleon fossil, and shows that features like the chameleon's projectile tongue was present deep in its ancestry," he added.